Metaplastic Tumour of the Breast: A case presentation

  • Khushboo Dewan Lady Hardinge Medical College, Delhi
  • Kiran Agarwal Lady Hardinge Medical College, Delhi
  • Om Prakash Pathania Lady Hardinge medical College
  • Shivali Sehgal Senior Resident Department of Pathology Lady Hardinge medical College
Keywords: Metaplastic carcinoma, Phyllodes tumour, Breast, Biopsy


Metaplastic carcinoma (MPC) is a rare breast neoplasm with an incidence of 0-2.5%.Metaplastic spindle cell carcinoma should always be considered in the differential diagnosis of atypical spindle cell proliferations of the breast. We describe the diagnostic challenge posed by a MPC (Spindle cell type) in differentiating it from a Phyllodes tumour (PT) with epithelial hyperplasia on a trucut biopsy. Conventionally, CK and Vimentin co-expression by spindle cells is taken as an evidence for a diagnosis of MPC, but recently, heterogenous CK expression by spindle cells in MPC has been described. Therefore, in such a setting it is not advisable to make a definitive diagnosis of either MPC or PT on a trucut biopsy. However, a few histological and immunohistochemical considerations may help us in deciding the diagnosis. Histologically, blending of squamous cells with spindle cells, presence of extensive lymphocytic infiltrate, keloid-like stromal areas and presence of DCIS, favour the diagnosis of MPC over PT. Absence of CK, EGFR, p63 expression and positive CD34 and bcl-2 expression by spindle stromal cells favours PT over MPC.

Author Biographies

Khushboo Dewan, Lady Hardinge Medical College, Delhi
Senior Resident Department of PathologyLady Hardinge medical College
Kiran Agarwal, Lady Hardinge Medical College, Delhi
Professor Department of PathologyLady Hardinge medical College
Om Prakash Pathania, Lady Hardinge medical College
Professor Department of SurgeryLady Hardinge medical College


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Case Report